Converter, WEBP filter options defunct

[Tapio]

Hi,

I tried 4 different settings for WEBP output in the batch converter.

Filter strength and filter sharpness:
25 - 0
25 - 7
60 - 0
60 - 7

Files seem to be almost exactly the same. 2 of 4 files differ in length by 2 bytes. My eyes do not find any difference at all.

So - it is not working?

XNView 0,99,4/64 Windows 10.

[Tapio]

Same problem in XNConvert, both versions up to date.

[xnview]

it depends on image, i have the same result as cwebp

[Tapio]

it depends on image, i have the same result as cwebp

Are you really sure? Maybe you use broken libraries? It happened to all pictures I tested. It was forest scenery. Now I tried a totally different picture. A screenshot.

One is saved with filter=100, one with filter=0. Result: 2 bytes of difference as well. It's always 2 bytes difference. EDIT: This is on compression method 6. On compression method 2 the difference is 4 bytes.

Pictures were saved with XNView via "Save As".

I was not able to produce images with noticable differences in their results. If it is this way, you could remove the filter options.

[xnview]

do you have tried with cwebp?

[Tapio]

do you have tried with cwebp?

No, where can I get it, is there a Windows binary?

[masterjp]

https://developers.google.com/speed/webp/download

You can get the official WEBP encoder/decoder exe on the Google website for Windows and other operating systems.

[Tapio]

https://developers.google.com/speed/webp/download

Thank you. Indeed, cwebp produces the same sized output. I cannot see under which circumstances the filter options do something significant. Visually I do not see a difference at all. Test image was landscape scenery with grass.

Code: Select all

C:\Users\Tapio\Desktop\libwebp-0.4.1-windows-x64\bin>cwebp -f 0 20171113_110319.jpg -o out1.webp
Saving file 'out1.webp'
File:      20171113_110319.jpg
Dimension: 3840 x 2160
Output:    874194 bytes Y-U-V-All-PSNR 37.58 46.14 49.20   39.12 dB
block count:  intra4: 31166
              intra16: 1234  (-> 3.81%)
              skipped block: 15 (0.05%)
bytes used:  header:            407  (0.0%)
             mode-partition: 159712  (18.3%)
 Residuals bytes  |segment 1|segment 2|segment 3|segment 4|  total
    macroblocks:  |       3%|      19%|      43%|      33%|   32400
      quantizer:  |      36 |      32 |      26 |      19 |
   filter level:  |       0 |       0 |       0 |       0 |

C:\Users\Tapio\Desktop\libwebp-0.4.1-windows-x64\bin>cwebp -f 100 20171113_110319.jpg -o out2.webp
Saving file 'out2.webp'
File:      20171113_110319.jpg
Dimension: 3840 x 2160
Output:    874196 bytes Y-U-V-All-PSNR 37.58 46.14 49.20   39.12 dB
block count:  intra4: 31166
              intra16: 1234  (-> 3.81%)
              skipped block: 15 (0.05%)
bytes used:  header:            411  (0.0%)
             mode-partition: 159711  (18.3%)
 Residuals bytes  |segment 1|segment 2|segment 3|segment 4|  total
    macroblocks:  |       3%|      19%|      43%|      33%|   32400
      quantizer:  |      36 |      32 |      26 |      19 |
   filter level:  |      19 |      12 |      11 |       8 |

C:\Users\Tapio\Desktop\libwebp-0.4.1-windows-x64\bin>cwebp -f 0 -sharpness 0 20171113_110319.jpg -o out3.webp
Saving file 'out3.webp'
File:      20171113_110319.jpg
Dimension: 3840 x 2160
Output:    874194 bytes Y-U-V-All-PSNR 37.58 46.14 49.20   39.12 dB
block count:  intra4: 31166
              intra16: 1234  (-> 3.81%)
              skipped block: 15 (0.05%)
bytes used:  header:            407  (0.0%)
             mode-partition: 159712  (18.3%)
 Residuals bytes  |segment 1|segment 2|segment 3|segment 4|  total
    macroblocks:  |       3%|      19%|      43%|      33%|   32400
      quantizer:  |      36 |      32 |      26 |      19 |
   filter level:  |       0 |       0 |       0 |       0 |

C:\Users\Tapio\Desktop\libwebp-0.4.1-windows-x64\bin>cwebp -f 0 -sharpness 7 20171113_110319.jpg -o out4.webp
Saving file 'out4.webp'
File:      20171113_110319.jpg
Dimension: 3840 x 2160
Output:    874194 bytes Y-U-V-All-PSNR 37.58 46.14 49.20   39.12 dB
block count:  intra4: 31166
              intra16: 1234  (-> 3.81%)
              skipped block: 15 (0.05%)
bytes used:  header:            407  (0.0%)
             mode-partition: 159712  (18.3%)
 Residuals bytes  |segment 1|segment 2|segment 3|segment 4|  total
    macroblocks:  |       3%|      19%|      43%|      33%|   32400
      quantizer:  |      36 |      32 |      26 |      19 |
   filter level:  |       0 |       0 |       0 |       0 |

[masterjp]

It is possible, that you use a very old webp encoder (version 0.4.1)? Your folder is named libwebp-0.4.1-windows-x64.

The latest webp library has the number 1.2.1 and you can find it here:

https://storage.googleapis.com/download ... ws-x64.zip

Although there is a new release candidate 1.2.2 version available:

https://storage.googleapis.com/download ... ws-x64.zip